I-864 Filling Fees and Address to Send

[hirshah]

Hi. I recently applied for Adjustment of Status (AOS) domestically based on my family based immigration. I have two sponsors, one primary and other is a joint sponsor. That means there are two I-864 forms that are filled. I just saw on the USCIS website that we need to send a check for this filing. I have sent my AOS documents to Chicago Lockbox address, but forgot to send the check related to Affidavit of Support.

What should be the amount of this check? Whom should it be payable to? Where should it be sent?